Calculation update! New properties have been added to the website for dislocation monopole core structures, dynamic relaxes of both crystal and liquid phases, and melting temperatures! Currently, the results for these properties predominately focus on EAM-style potentials, but the results will be updated for other potentials as the associated calculations finish. Feel free to give us feedback on the new properties so we can improve their representations as needed.
Warning! Note that elemental potentials taken from alloy descriptions may not work well for the pure species. This is particularly true if the elements were fit for compounds instead of being optimized separately. As with all interatomic potentials, please check to make sure that the performance is adequate for your problem.
Citation: A. Mahata (2026), "Development and validation of interatomic potential for Sc and Al-Sc alloys: Thermodynamics, solidification, and intermetallic ordering", Computational Materials Science264, 114443. DOI: 10.1016/j.commatsci.2025.114443.
Abstract: We present a second-nearest-neighbor Modified Embedded Atom Method (2NN-MEAM) potential for Scandium (Sc) and Aluminum-Scandium (Al-Sc) alloys that unifies cohesive, thermodynamic, and solidification behavior within a single transferable framework. The Sc component accurately reproduces cohesive energy, lattice constants, defect energetics, and the experimental melting point obtained from two-phase coexistence, demonstrating reliable description of both hcp and liquid phases. The Al-Sc binary interaction parameters were fitted using the L12-Al3Sc reference and benchmarked against first-principles and calorimetric data. The potential reproduces the strong negative formation enthalpy of Al3Sc (-0.45 eV atom-1), correct relative stability of competing phases, and realistic elastic properties. Mixing enthalpies of the liquid alloy agree with ideal-associated-solution and CALPHAD models, confirming that the potential captures exothermic Al-Sc association in the melt. Molecular-dynamics simulations of solidification reveal the expected temperature and composition dependence of homogeneous nucleation. Pure Al crystallizes readily, while Al-1 at.% Sc exhibits a longer incubation and slower growth at the same absolute temperature due to reduced undercooling and solute drag. Within the alloy, ordered Al3Sc-type L12 embryos appear spontaneously, with Sc atoms occupying cube-corner (B) sites surrounded by twelve Al neighbors. Energy-volume trajectories confirm that the potential links thermodynamics to microstructural evolution. Overall, the developed 2NN-MEAM potential provides a quantitatively grounded basis for modeling melting, solidification, and intermetallic ordering in Sc and Al-Sc systems, enabling future multicomponent alloy design and large-scale nucleation studies.
Notes: This potential was developed by Avik Mahata, Merrimack College, North Andover, MA. The potential uses the second-nearest-neighbor MEAM (2NN-MEAM) formalism. The potential was developed for atomistic simulations of Sc, with particular emphasis on cohesive and structural properties, thermodynamics, melting and solid–liquid coexistence, solidification and homogeneous nucleation. The potential reproduces the experimentally established hcp structure and gives a melting temperature of approximately 1814 K and an enthalpy of fusion of 16.1 kJ/mol.
See Computed Properties Notes: These files were provided by Avik Mahata on Sept 5, 2026. The potential and supporting LAMMPS materials are also publicly available through the github repository link. File(s):
Citation: R.S. Elliott, and A. Akerson (2015), "Efficient "universal" shifted Lennard-Jones model for all KIM API supported species".
Notes: This is the Sc interaction from the "Universal" parameterization for the openKIM LennardJones612 model driver.The parameterization uses a shifted cutoff so that all interactions have a continuous energy function at the cutoff radius. This model was automatically fit using Lorentz-Berthelotmixing rules. It reproduces the dimer equilibrium separation (covalent radii) and the bond dissociation energies. It has not been fitted to other physical properties and its ability to model structures other than dimers is unknown. See the README and params files on the KIM model page for more details.
Citation: A. Mahata (2026), "Development and validation of interatomic potential for Sc and Al-Sc alloys: Thermodynamics, solidification, and intermetallic ordering", Computational Materials Science264, 114443. DOI: 10.1016/j.commatsci.2025.114443.
Abstract: We present a second-nearest-neighbor Modified Embedded Atom Method (2NN-MEAM) potential for Scandium (Sc) and Aluminum-Scandium (Al-Sc) alloys that unifies cohesive, thermodynamic, and solidification behavior within a single transferable framework. The Sc component accurately reproduces cohesive energy, lattice constants, defect energetics, and the experimental melting point obtained from two-phase coexistence, demonstrating reliable description of both hcp and liquid phases. The Al-Sc binary interaction parameters were fitted using the L12-Al3Sc reference and benchmarked against first-principles and calorimetric data. The potential reproduces the strong negative formation enthalpy of Al3Sc (-0.45 eV atom-1), correct relative stability of competing phases, and realistic elastic properties. Mixing enthalpies of the liquid alloy agree with ideal-associated-solution and CALPHAD models, confirming that the potential captures exothermic Al-Sc association in the melt. Molecular-dynamics simulations of solidification reveal the expected temperature and composition dependence of homogeneous nucleation. Pure Al crystallizes readily, while Al-1 at.% Sc exhibits a longer incubation and slower growth at the same absolute temperature due to reduced undercooling and solute drag. Within the alloy, ordered Al3Sc-type L12 embryos appear spontaneously, with Sc atoms occupying cube-corner (B) sites surrounded by twelve Al neighbors. Energy-volume trajectories confirm that the potential links thermodynamics to microstructural evolution. Overall, the developed 2NN-MEAM potential provides a quantitatively grounded basis for modeling melting, solidification, and intermetallic ordering in Sc and Al-Sc systems, enabling future multicomponent alloy design and large-scale nucleation studies.
Notes: This potential was developed by Avik Mahata, Merrimack College, North Andover, MA. The potential uses the second-nearest-neighbor MEAM (2NN-MEAM) formalism. The potential was developed for atomistic simulations of Sc and Al–Sc systems, with particular emphasis on cohesive and structural properties, thermodynamics, melting and solid–liquid coexistence, solidification and homogeneous nucleation, liquid Al-Sc mixing thermodynamics, and Al3Sc intermetallic ordering. For elemental Sc, the potential reproduces the experimentally established hcp structure and gives a melting temperature of approximately 1814 K and an enthalpy of fusion of 16.1 kJ/mol. For the Al-Sc binary system, it reproduces the strongly negative formation enthalpy of L12-Al3Sc (approximately −0.451 eV/atom), the relative stability of important Al-Sc intermetallic phases, and high-temperature liquid mixing behavior.
See Computed Properties Notes: These files were provided by Avik Mahata on Sept 5, 2026. The potential and supporting LAMMPS materials are also publicly available through the github repository link. File(s):
Citation: H.-H. Ahn, J. Hur, G. Xu, and W.-S. Ko (2026), "Atomistic insights into structural ordering effects on martensitic transformations in Mg-Sc shape memory alloys", Acta Materialia306, 121929. DOI: 10.1016/j.actamat.2026.121929.
Abstract: Mg-Sc shape memory alloys exhibit exceptionally low density but suffer from very low transformation temperatures. Here, we combine first-principles calculations, phonon analysis, molecular dynamics simulations, and hybrid Monte Carlo/molecular dynamics to uncover the atomic-scale mechanisms governing phase transformations in Mg-Sc alloys. Our results reveal that partial atomic ordering is essential for reversible martensitic transformations, with partially ordered B2 austenite and B19 martensite structures being thermodynamically favored over their disordered counterparts across compositions of 15-25 at.% Sc. This ordered transformation pathway exhibits remarkable composition sensitivity: reducing Sc content progressively stabilizes martensite relative to austenite, driving increases in the transformation temperature consistent with reported experimental trends. This comprehensive atomistic understanding provides a clear strategy for developing ambient-temperature lightweight SMAs through compositional optimization and controlled ordering.
See Computed Properties Notes: These files were provided by Won-Seok Ko on June 2, 2026. The README.md file contains usage notes, element ordering, reference structures, and recommended cutoff values. File(s):